2014-09-18

basics of thermodynamics-part-11

What is adiabatic saturation temperature?
It is the temperature at which the outlet air can be brought into saturation state by passing through the water in the long insulated duct (adiabatic) by the evaporation of water due to latent heat of vaporization.

What is psychrometer?
Psychrometer is an instrument which measures both dry bulb temperature and wet bulb temperature.

What is psychrometric chart?
It is the graphical plot with specific humidity and partial pressure of water vapour in y axis and dry
bulb temperature along x axis. The specific volume of mixture, wet bulb temperature, relative
humidity and enthalpy are the properties appeared in the psychrometric chart.

What is sensible heat and latent heat?
Sensible heat is the heat that changes the temperature of the substance when added to it or when
abstracted from it. Latent heat is the heat that does not affect the temperature but change of state occurred by adding the heat or by abstracting the heat.

What is degree of saturation?
It is the ratio of the actual specific humidity and the saturated specific humidity at the same
temperature of the mixture.


What is dew point temperature?
The temperature at which the vapour starts condensing is called dew point temperature. It is also equal to the saturation temperature at the partial pressure of water vapour in the mixture. The dew point temperature is an indication of specific humidity.

What is meant by dry bulb temperature (DBT)?
The temperature recorded by the thermometer with a dry bulb. The dry bulb thermometer cannot affect by the moisture present in the air. It is the measure of sensible heat of the air.